{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T18:08:06Z","timestamp":1789495686669,"version":"build-2803163510"},"reference-count":24,"publisher":"Public Library of Science (PLoS)","issue":"9","license":[{"start":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T00:00:00Z","timestamp":1789430400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>Patients with skeletal Class III malocclusion may have limited alveolar support around the mandibular incisors, but conventional cephalometric measures do not directly describe the root-alveolus relationship. This retrospective cross-sectional study quantified labial and lingual alveolar bone thickness and examined whether signed IA-PAMD indicated apical root position within the symphysis. Pretreatment cone-beam computed tomography and lateral cephalometric records from 80 untreated patients (320 incisors) with signed ANB\u2009&lt;\u20090\u00b0 were analyzed. Bone thickness was measured at three root levels. Correlations and cluster-robust multivariable models adjusted for tooth, age, sex, signed ANB, GoGn-SN, and incisor mandibular plane angle. Mean labial thickness was 0.36, 0.49, and 2.40 mm at the cervical, middle, and apical levels; corresponding lingual values were 0.59, 1.39, and 4.01 mm. Labial bone was thinner than lingual bone (all P\u2009&lt;\u20090.001), and labial thickness was below 0.5 mm in 80.3% of cervical and 63.4% of middle-root observations. Signed IA-PAMD correlated positively with labial apical thickness, negatively with lingual apical thickness, and not with total apical width. In adjusted models, each 1\u00b0 increase in signed IA-PAMD was associated with 0.084 mm greater labial apical thickness (95% CI, 0.053\u20130.115), 0.092 mm lower lingual apical thickness (95% CI, \u22120.141 to \u22120.043), and no difference in total apical width (\u22120.008 mm; 95% CI, \u22120.082 to 0.065). The mirror-image labial and lingual coefficients, together with the near-zero total-width coefficient, support interpretation of signed IA-PAMD as a measure of root-apex eccentricity within the symphysis rather than aggregate apical bone support. It should not be interpreted as a treatment target or safety threshold, and the absence of a Class I comparator limits conclusions specific to skeletal Class III morphology.<\/jats:p>","DOI":"10.1371\/journal.pone.0358261","type":"journal-article","created":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T17:45:08Z","timestamp":1789494308000},"page":"e0358261","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Mandibular incisor alveolar housing and incisor-alveolar axis relationship in untreated skeletal Class III malocclusion: A cross-sectional CBCT study"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0009-0000-4431-7171","authenticated-orcid":true,"given":"Thanh Huyen","family":"Nguyen","sequence":"first","affiliation":[{"name":"National Hospital of Odonto-Stomatology Hanoi","place":["Hanoi, Vietnam"],"department":["Department of 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